This invention relates to a safety device for a vehicle, and more particularly to a safety device which is suited to automatically apply electric braking in case of running on a downward slope.
Where an electromobile, a battery fork lift or the like travels on a downward slope, the vehicle velocity increases even when an accelerator is kept released. Although the driver or operator of the vehicle actuates braking means with attention on a steep slope, it is often the case on a comparatively gentle slope that the driver or operator does not conduct the braking operation. Even on the gentle slope, however, the vehicle velocity can become great when the traveling is left as it is. If the braking operation is made in a flurry in such case, there will be the danger of causing lateral turning or the like accident.
In one case, there is considered a method in which braking is applied by sensing the inclination angle of the running path. However, there is not any inclination angle sensor suitable for the vehicle. For example, a mercury switch operates erroneously due to the vibration of the vehicle or to an acceleration change at a quick acceleration or deceleration. Any other proposed sensors such as the pendulum type sensor are not suitable for the vehicle, either.